CA1050065A - Intermittent web advancing apparatus - Google Patents

Abstract

INTERMITTENT WEB ADVANCING APPARATUS

Abstract of the Disclosure An apparatus for use in advancing a web strip, which may be unperforated, along a path and including a guideway for defining at least a part of such path and a reciprocatable shuttle in combination with a friction pad operable to engage a face of said web to advance the web along the path.

Description

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This is a division of Serial No . 161, 548 filed January L~, 1973, a divisio~ or ~:;erial No. 11;~,89~ filed May 13, 1971.
~ he pre ent inven~ion relates to a perfor~tor ~or punchlng ~ series of holes along the length of a web as it is ~ntermlttently advanced, and particularly to such a perf~rator ~hich perforates film strips at a rate much grea er than here~
tofore possible and which is adaptable to different film fonnats and ~ilm widths.
Continuous and intermittent perfor~tors ha~e been used in the art to perforate a row of perforations in succession ~long the length of a web or fllm. In the manufacture of motion picture f~lm, where a high degree of accuracy ~ s required in the f~rmation of the perforations, per se, and the pitch therebetween ~t hs~ been the usual practice to use perforators haYing a single ~rame intermitten~ shuttle ad~ance in c~mbination with a pilot pinO In such perforators, the film ~ s in~erm1ttently sdvanced through a perforating station by a shuttle mechanism having a claw which engages a perforation in the film previously m~de by a reciprocal punch whic~ acts on the film in the perforating station ~ile the film is stationary. To insure high accur8cy ~n the pitch between perforations, a pilot pin is associated with the punch to move therewith. This pilot pin is located bet~een the punch and shuttle mechanisms by z distance from the pu~ch equal to one perforation pitch, and is arranged to enter the perforatlon pre~ously made by the punch just be-fore the punch engages the filsQ so as to accura~ely adjust the film advance before a succeeding perforation is made. The pilot pin which is formed to accurately fit a previously made

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perforation is provided to correct for any slight i~accuracy in film ad~ance which might be made by the shuttle mechanism.
While perforators of the type having a single frame intermittent shuttle advance with pilots are known to possess high accuracy, they are limited as to ~he speed at which they can be operated because the conventional cam and follower designs they ha~e used in the shuttle mechanism will not stand up for a reasonable le~gth of time u~der the high accelerations involved in high speed operation. Furthermore, conventional cam and follower designs used in shuttle mechanisms are subject to severe wear, lubrication and heat generation problems, while ball bearing followers are generally too massive and short in life. Another shortcoming of known perforators of this type has been the necessity of temporarily splicing the end of a new web onto the end of an expiring web, or providing the end of the new web with two or more perforations, in order to thread a new web onto the perforator. Also, intermittent film perforators of the type mentioned have had a top speed of about

3,580 perforations per minute and have been designed to handle one format of film, e.g. 35mm, 16mm, 8mm, and/or super 8.
Thus, in accordance with the present teaching, a film advancing assembly is provided for intermittently feeding and unperforated film strip through a siven path. The assembly comprising a curved film guideway defining a portion of the path and including edge guides for guiding the edges of film.
Means are provided for intermittently frictionally gripping the film and advancing it through the guideway and includes the shuttle which reciprocates through a path including a film advancing stroke and a return stroke. A film supporting member is provided engageable with one surface of th~ fiim at the B

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guideway with the film supporting mPmber being mounted to reciprocate along the cur~ed portion of the film path. A film engaging jaw is proYided on the shuttle ana which is adapted to engage-the other face of the film and tinge the film against the supporting member. Means are provided for reciprocating the shuttle through fiLm advancing and return strokes and for causing the film engaging jaw to move into pressing engagement with the other face of the film at the beginning of and during the film advancing stroke of the shuttle to advance the film during the return stroke with means connecting the shuttle supporting member with the shuttle so that the film supporting member is reciproca~
ted by the shuttle and in synchronism therewith.
The novel features which I considex characteristic of my invention are set forth wi~h particularity in the appended claims. The invention itself, however, both as to its organi-zation and its methods of operation, together with additional objects and advantages thereof will best be understood from the following description of specific embodiments when read in con-nection with the accompanying drawings in which:
Figure 1 is a fron~ ele~ational view of the punch and thread-up shuttle mechanism of a perforating device constructed in accordance with a preferred embodiment of the present inv~ntion with the front frame of the device being partly broken away for purposes of clarity;

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Figure 2 is a transverse sec~ional view taken sub--stant~ally along line 2-2 of F~gure 1, and show~ng the main shaft assembly;
Figure 3 is a sectional view of the punch and thread-up shuttle mechanism of the perforating device taken substantially along line 3-3 ~f Figure 2;
Figure 4 is a top view taken substantially along the line 4-4 ~f Figure 3;
Figure 5 shows a schematic of the high speed shuttle sho~ing the relationship between the upper cam, the flat cam, the shuttle tooth path, the film plane, and the eccentri~ drive shaft;
Figure 6 shows plots of shuttle claw paths necessary for the perforation of 35mm, Super 8, and regular 8 film formats;
Figure 7 is a transverse sectional view taken sub-stantially along the line 7-7 of Figure 1, and showing the - thread-up shuttle assembly.
Figure 8 is a fragmentary sectional vlew taken sub-stantially alDng the line 8-8 of Figure 1, and sh~wing bearing assemblies for the thread-up shuttle.
Figure 9 is a transverse sectional view taken sub-stantially along the line 9-9 of Figure 1, and showing the thread-up shuttle film engagement area.
Figure lQ is a top ~iew ~f Figure 7 with the strippers removed and showlng edge guiding and die arrangements necessary to perforate regular 35 mm film.

1~500~5 Figure 11 is a schernatic of the thread--lp shuttle mechanism shot~ing the geometrical rela~ionships of the eccentric drive shaft, the engagement arm pivot point, and the film engagement area.
Figure 12 shows the electrlcal control diagram for both thread-up and high speed operatlons;
Figure 13 is a schematic v;ew of a modification of the perforator high speed shuttle mechanism adapted for use in an amateur motion picture camera;
Figure 14 is a schema~ic view of a modification of the perforator high speed shuttle mechanism adapted for use in an amateur projector.
Figure 15 is a schematic view of a modification of the perforator thread-up shuttle mechanism adapted f~r use in an amateur camera.
F$gure 16 is a schematic view of a modification of the perforator thread-up s~uttle mechanism adapted for use in an amateur prDjector.
Figure 17 is a schematic showing of another modifi-cation of the perforator thread-up shuttle mechanism adapted for use in an amateur camera.
Figure 18 is a schematic showing of a modification of the embodiment of the perforator thread-up shu~tle mechanism shown in Figure 17 which is adapted for use in an amateur mot~n picture projec~or.
Generally, the present film perforator comprises a perforating station at which a reciprocating punch acts on the ~ 6 5 film while it is stat~onary. The film strip ls intermitten ly advanced to and throu~h the perfor~ting s~ati~n by a shuttle mechanism including one or more claws which engage the perforation(s) Tade at ~he perforating stati~n and advance the fllm one framé at a time. Associated with the punch, and ~ocated between it and the point w~ere the shuttle engages the f~lm, is a pilDt pin which engages a previously made perforation while the film is stationary and just before the punch engages the film ~o perforate it. This pilot pin is shaped to accurately fit the perforation and is spaced from the punch a distance which is equal to the pitch spacing desired bet~7een ~he - perforations. The purpose of the pilot is to accurately position the film just before the punch makes a successive perforat;on so as to be assured the pitch between su~cessive perforations is exactly the same. It does this by correcting ~ny inaccuracy there might possibly be in the pull-down stroke of the shuttle mechanism or for any movement of the film whi h might occur as or after the shuttle claw leaves film perfor-ations. The parts of the perforator are so designed and mounted that it is adaptable to different film formats and w~dths.
So that a new film can be threaded into the perforator without having the leading end temporarily spliced to the trailing end of an expiring film, or without having to provide the leading end of a new film with perforations, the perforator is provided with an automatic threading mechanism. This comprises an inter-mittent film feeding mechanism which operates in synchronism ~ 5~ ~ 6 S

w~th the punch an~ shuttle feed and frictionally engages the film to feed it intermittently one frame at a time to and through the punch mechanism to the shuttle mechanism. This automatic thread-ing mechanism is selectively operated at a speed below the top speed of the perforatvr and cannot be activated unless the perf~-rator has been disconnected from the high speed power source for a time greater than a preselected time delay to insure that the machine has stopped. The automatic threading mechanism is combined with the perforator so that after the shuttle mechanism lo has assumed control of the film leaving the punching station the automatic threading mechanism will be automatically disengaged and the perforator can be brought up to top speed.
It is p~inted out that the key element in this perforator design is the shuttling mechanism which moves the film intermittently at a rate as high as 12~0Q0 perforations per minute without damage, and which operates with accuracy and low maintenance over a long span of life. Since the acceleration of a reciprocating mechanism increases as the square of the speed and linearly with the distance traveled, it has been found that the shuttle mechanism for feeding a 35mm film is subjected to accelerations which are over seven ~7) times those for a shuttle fDr a 16mm film running at 3,580 rpmO Because of the high accelerations involved, it was found impossible to use conven-tional cam and follower designs for shuttle mechanisms operating at speeds as high as 12,000 perforat~ons per minute because slid-~ng follower members are subject to severe wear, lubrication, and heat generation problems. The shuttle mechanism designed :~L050065 ~or this perforator utilizes very light aluminum parts w~ich ~re symetrically loaded. A rocker cam and flat cam arrangement which is used to control the claw tip to the desired path of travel incurs very little slippage (relative sliding movement Gf the cooperating sur~ace of the cams) and, therefore, has a long life even though fabricated of lightw~i&h~ ma~erials. The flat cam is mounted in an aluminum carriage which extends length-wise of the film path. The carriage is supported by two groups of vertical suspension springs which are tuned to the operating speed of the carriage. The shuttle arm is driven through ball bearings by an eccentric at one end. The rocker cam is attached to the shuttle arm and contacts the flat cam. A coupling spring tr~nsmits h~rizontal motion from the shut~le arm to the carriage member in such a manner as to produce negligible slippage be-tween the cams, and also maintains proper contact pressure be-~æen the cams. It has been fc>und that the design of this shuttle mechanism for Super 8 film (pitch 0.1667'7) is also sa~isfactory for 35mm film (pitch 0.187~), and for 8mm film (pitch 0.150").
The ~nly change required is the eccentricity of the drive and 20 the shape and size of the claw tooth member(s3 of the shuttle.
Referring now to the drawings, and initially to Figures 1, 2, 3, and 7 thereof, it will be seen that a perfora-ting device embodying the present invention has a base plate 23 attached to base block 20 by any suitable means (not shown).
The side plate 25 (shown in Figure 73 and back side plate 27 (see Fi~ure 7) are attached to base plate 23 by any suitable means (not shown). Spring holder 32 is attached to base plate 23 by ~ 10 -1~5~:)65 ~ny suitable means, (not shown). Two flat parallel springs 35 are attached at one end to spring holder 32 by clamping strips 37 and bolts 39. Springs 35 are attached at the other end to punch support 45 by clamping strips 41 and bolts 43. The purpose of clamping strips 37 and 41 is to rigidly hold the ends of springs 35 so that the desired bend-ing behavior of springs 35 is obtained. Flat spring 46 is attached to spring holder 32 by clampin~ strip 47 and bolts 49. Punch truss 59 is attached at one end to punch support 45 by bolts 53 which pass through flat spring 46 and thread into clamping strip 51. Punch holder 57 is attached to punch support 45 by bolts 53 which pass through flat sprlng 46 and thread into clamping strip 51. The purpose of clamping strips 47 and 51 is ~o rigidly hold the ends of flat spring 46 so - that the desired bending behavior of flat spring 46 is obtained.
Punch support 45 is free to pivot about the inter-~ection of the plane of flat parallel springs 35 and of the plane of t~e flat spring 46. The pivot axis thus formed by the intersection of the flat paràllel springs 35 and flat spring 46 may be considered as fixed in space the same as a rigidLy mounted hinge.
This type of spring hinge differs from a conventional - hinge in three important respects. First, there is no play in the spring hi~ge and no play-can develop as a result of wear or loss of vil film; second, no lubrication is required, ~ndl therefore 3 maintenance is reduced and the danger of oil getting on the film and in helping to attract dirt accumula-tion is minimized; and, third, the springs do not create a ~ ~ 50 ~ ~ S
friction torque and do produce a res~orin~ torque prDportional to the angle of displacement from the neutral position or zero stress position. In actual practice, this restoring torque has no detrimental effects but is actually used to tune assemblies to supply sinusoidal acceleration torque at the operating speed of the perforator. The length and thiek-ness of flat parallel springs 35 and flat spring 46 must be chosen to keep the operating stress well below the endurance limit of the spring material.
One end of connecting spring 61 is attached to the other end of punch truss 59 by bolts 63. The other end of connecting spring 61 is attached to punch driver arm 67 by bolts 63'. Punch driver anm 67 is rotatably attached to eccentric drive shaft 69 which is suitably eccentrically journaled to rotate and is supported by front bearing plate 71 (as shown in Figure 2) and rear bearing plate 73 (see Figure 2) by a bearing assembly which will be described in more detail with reference to Figure 2. Bolts 75 (as shown in Fi~ure 2) attach front bearing plate 71 to base block 20, and bolts 76 (see Figure 2) attach rear bearing plate 73 to base block 20.
LRt us now consider Figure 2, which shows the main drive shaft assembly in detail. This assembly is discussed in c~nsiderable detail in order to show how the film perforator can be readily adapted to perforate different film formats and f~lm widths. The configuration in Figure 2 is that necessary t~ perforate 35mm film. Main ball bearing 84 is fitted on ~ 050~65 eccentric drive shaft 69 and constrained axially at the outer race by end cap 80 and dirt seal plate 88 which clamps against bearing plate 73 by action of bo1ts 82. Flexible coupling 90 is a~tached to eccentric drive shaft 69 by screw 92. The purpose of flexible coupling 90 is t~ allow for slight mis-alignment bet~een eccentric drive shaft 69 and the motor drive shaft (not shown3. The screw 92 clamps the right end portion of the coupling against the inner race of main bearing 84 and spacer 86 thus c~nstraining the eccentric shaft in the axial direction. Split ball Dearing 94 is fitted on an eccentric portion 95 of the drive shaft 69 and pressed int~ punch driver arm 67. Oil shields 96 and 98 are pressed into punch driver arm 67. Back shuttle spacer 100 is then slid onto eccentric drive shaft 69 and constrained axially in one direction by split ball bearing 94 and axially in the ot~er direction by split ball bearing 104. Shuttle arm 102 is journaled to rotate re-lative to eccentric portion 99 ~f the drive shaft 69 between spacers 10~ and 112 through a bearing assembly that is comprised . of two split ball bearings 104, two oil shields 106, and spacers 108 and 110. Front shuttle spacer llZ is fitted on eccen~ric drive shaft 69 and constrained axially in one direction by split ball bearing 104 and axially in the other direction by split ball bearing 119. Split ball bearing Ll9 is fitted onto counterweight sleeve 114 which is sli.d onto eccentric drive shaft 69. Main ball bearing 120 fits into end spacer 116 and is also fltted o~er c~unterweight sleeve 114. End spacer 116 is then ~ 05~ 5 rigidly attached to front bearing plate 71 by screws 118. Nut 122 threads onto eccentric drive shaft 69, and is used to tighten the entire shaft assembly together. End cap 124 is rigidly attached t~ end spacer 116 by screws 125 and the outer race of bearing 120 is clamped in the process.
The eccentricity ~f eccentric drive shaft 69 at the shuttle bearings 104 for the 35mm film application is a little more than 1/2 of the pitch of 35mm film which pitch is .0935 in.
The small excess of the order o 0.007 in. allows for bearing clearance and deflection and insures easy entrance of the claw with-out scuffing against the perforation edge. If film having a different pitch is desired to be perforated, the only changes that need to be made in the main drive shaft assembly as shown in Figure 2 is that eccentric drive shaft 69 must be replaced by one having the de~ired eccentricity at the bearing~ 94 and 104, counterweight sleeve 114 must be replaced by one having the proper geometry, and the counterweight portion 114 of eccentric shaft 69 is also suitably altered. Back shuttle spacer 100 must also be suitably altered~
If it is desired to perforate Super 8 film, the eccentricity of 20 eccentric drive ~haft 69 at bearings 94 and 104 muQt be 0. 0834 in. plus overage allowance, and f~r regular 8mm film the eccentricity must be .075 in. plus allowance. Of course, the size and shape of the claw tooth members of the shuttle and the punch and die arrange-ment must als~ be appropriately changed in order to perforate film of different widths and different formats.
Spacer sleeve 126 is slid over lower shaft 127 (as shown in Figure 3~ which is rigidly a~tac~ed to front bearing plate 71

5~ 0 ~ 5 ~nd rear bearing plate 73 by bolts (not shown). The purpose - ~f this arrangement is to ~nsure that proper spacing is maintained between bearing plates 71 and 73.
As shown in Figure 3, two punches 130 one for each margin of the fllm a~e held in punch holder 57 by set screws 132, which are shown in more detail in Figure 4. Two pilot pins 134, one for - ~he perforations at each margin of the film, are held in punch holder 57 by set screws 136 (see Figure 4). Punch holder 57 is attached to punc~ truss 59 by bolts 137 and 53~ Top plate 138 is attached to front bearin~ plate 71 and rear bearing plate 73 by any suitable means (not shown~. Three parallel leaf springs 140 appropriateiy spaced by washers 142 and constrained by clamping spacer 144 are attached to top plate 138 by bolts 146. The other end ~f parallel springs 140 are appropriately spaced by washers lS0 and constrained by clamping spacer 152 and a~ached to flat cam carriage 148 by bolts 154. The purpose of clamping spacer 144 is to rigidly attach flat parallel springs 140 ~o top plate 138 and to insure the desired bending behavior of parallel springs 140. The purpose of clamping spacer 152 is to rigidly ~ttach parallel springs 140 to flat cam carriage 14~ and to insure proper bending behavior of parallel springs 140.
The other end of flat cam carriage 148 is attached by bolts 162 to one end of three parallel springs 1~6 whose ends are ~pprcpriately spaced by washers 164 and constrained by clamping spacer 166 and attached to top plate 138 by bolts 168. The pur-pose of clamping spacer 160 is to rigidly attach parallel springs 156 to flat cam carriage 148 and to insure the proper bending be-~ 15 -~ 0S0065 havior of ~lat parallel springs 156. The purpose of clamping ~pacer 166 is to rigidly attach parallel springs 156 to top plate 138 and to insure the proper bending behavior of parallel springs 156. Flat cam 149 is rigidly cemented into ~lat cam carriage 148.
Rocker cam 180 is attached to shuttle arm 102 by screws 182. Shuttle bracket 185 is attached to shuttle arm 102 by bolts 186. The film is intermittently advanced through the per-forating station by two shuttle claws or teeth 184 on shuttle bracket 185 of the shuttle mechanisms, each of which engages a perforation in the film previously made by a respective reciprocal punch 130 which acts on the film in the perforatinv ætation while the film is stationary.
To insure high accuracy in the pitch of the perforations, pilot pins 134 re associated with the punches 130 and move there-w~th. Pilot pins 134 are located between punches 130 and shut~le teeth 184 by a distance equal to one perforation pitch from the punch and are arranged to enter the perforations previously made - by the punches just before the punches engage the film so as to accurately adjust the film advance before succeeding perfora-tlons are made. Pilot pins 134 are formed to accurately fit previously made perforations and their purpose is to correct for any slight inaccuracy ~n film advance which might be made by the shuttle mechanism.
The shuttle mechanism designated for this perforator ut~lizes very light~ight aluminum parts which are symmetrically ~oaded. The arrangement of rocker cam 180, flat cam 149, and 105()06S
flat cam carriage 148 which are used to control the motion of shuttle teeth 184 to the desired path of travel~ incurs ~.ery little slippage betw~en the cams 180 and 149, and, therefore) has a long life even though fabricated of lightweight material.
Flat cam carriage 148 extends lengthwise ~f the film path and is upported by tw~ groups of suspension springs 140 and 156, which are tuned to the operating speed of flat cam carriage 148. Shuttle arm 102 is driven through ball bearings 104 by eccentric shaft 69. Rocker cam 180 is integral with or attached to shuttle arm 102 and contàcts flat cam 149. Rocker cam 180 has an arcuate surface which rides on flat cam 149, and gives ~he required motiDn of shuttle teeth 184. U-shaped coupling spring 170 (see Figure 4) transmits motion from shuttle arm 102 to flat cam carriage 148 in such a manner as to produce negligible slippage between the cams 180 and 149, and also maintain proper contact pressure betw~en the cams at all speeds of operation of ~he shuttle mechanism.
As mentioned above, springs 140 and 156 are tuned to the operating speed for the mass of flat cam carriage 148 and all parts associated with its connection to the free ends of the flat - parallel springs 140 and 156. Flat cam carriage 148 slants at ~ubstantially 20 to the film path to make the acceleration pattern of the drive system for the flat cam carriage 148 approach 8 simple harmonic that can be, and is, tuned by the fla~ parallel springs 140 and 156.
The end of U-shaped coupling spring 170 that is attached ~ 0 50 0 6 S
to shuttle arm lG~ by bolts 172 is tilted slightly in a counter-clockwise direction relative to the remainder of the spring for maintaining conta et pressure between the cams at all speeds of operation.
The left end of punch truss 59 is operatively connected to eccentric drive shaft 69 through punch driver arm 67 and connecting spring 61. The other end of punch truss ~9 is p~votally mounted by crossed springs 46 and 35, which causes punches 130 to reciprocate across ~he film path to perforate the film.
Pil~t pins 134 are slightly longer than-punches 130 to enter previously formed perforations just as shuttle teeth 184 are leaving perforatîons and before punches 130 engage the film to insure the film being advanced the desired pitch before a pair of successive perforations is made therein.
The film is fed into the perforator through a guideway comprising a film apron 188 which is attached to base plate 23 by suitable means (not shown) and a film apr~n cover 190 attached to film apron 188 by suitable means (not shown).

The film leaving the perforating station passes through a guideway comprising a film apron 192 attached to base plate 23 by suitable means (not shown), and a film apron cover 194 attached t~ takeup side film apron 192 by suitable means (not ~hown).
Front die holder 196 (as shown in Figure 7~ and rear die holder 198 (see Figure 7) are attached to base plate 23 by ~uit~ble means (not shown). Punch side stripper 202 is sup-~ 5~D0 ~ 5 ported from the bottom by die holders 196 and 198 ~see Figure 7) and constrained in the upwards direction by strippcr clamp 204 (as shown in Figure 4) which is attached to front side plate 25 by screw 205, an~ by stripper clamp 206 (see Figure 4) which is attached to back side plate 27 by screw 207.
Take-up side stripper 200 is supported from the bottom by die holders 196 and 198 (see Figure 7) and eonstralned in t~e upwards direction by stripper clamp 208 (as shown in Figure 4) which is attached to front side plate 25 by bolt 209 (see Figure 4) and stripper clamp 210 (see Figure 4) which is attached to back side plate 27 by bolt 2Ll (see Figure 4). Spacer sleeve 213 (see Figure 3) is attached to front bearing plate 71 (not shown) and rear bearing plate 73 (not shown? by suitable means (not shown)O The purpose of spacer sleeve 213 is to insure the proper spacing between bearing plates 71 and 73.
As shown in Figure 4, pilot pin spacer 220 is loosely held between pilot pins 134 and punches 130. Pil~t pin wedges 222 and 224 are forced into grooves in pi~ot pin spacer 220 to . obtain fine adjustment of the lateral position of pilot pin spacer 220.
Figure 5 shows a schematic of the high speed shuttle showing the relationship b~tween rocker cam 180, 1at cam 149, path of point P on shu~tle teeth 184, the film plane, and eccentric drive shaft 69. The eccentricity of drive shaft 69 w~Ll be designated by e. As eecentric drive shaft 69 rotates ~n the direction showm, rocker cam 180 rides on flat cam 149, ~nd shuttle arm 102 and shuttle teeth 184 move in such a way as ~ 05006~
to cause point P on shuttle teeth 184 to move in the path ~hown schematically by the dotted line in Figure 5. IE should be noted that the total stro~e length during one stroke is equal to twice the eccentricity of eccentric drive shaft 69 Dr 2e.
Since flat cam 149 is coupled to shuttle arm 102 by U-shaped coupling spring 170 (as shol~ in Figure 4~ and is ~uspended by flat parallel springs 140 and 1569 flat cam 149 necessarily oscillates back and forth parallel to itself and moves up and down parallel to itself. This motion in combin-ation with the rocking motion of the areuate surfa~e of rocker cam 180 gives negligible slippage between cams and the desired motion of shuttle teeth 184.
As shown in Figure 5, at the starting point (angle e - o), the point 2 on rocker cam 180 is in contact with flat cam 149, and the reference point P on the shuttle teeth 184 is on the axis (horizontal line 0-0) with the value of x- e.
The drive point 3 rotates about the fixed point 7 at an eccentricity ~f e. To some extent the choices of dimensions and shape of rocker cam 180 are arbitrary, but they are largely dictated by consideration of the desired film pitch, the amount of in-and-out trave7 required to clear the stripper, the straightness of the path after full engagement, and the s~lare-ness of the corners without incurring excessive upward accelera tions. Wnile the cam 149 is described above as having a planar surface for cooperation with the convex surface of the r~cker cam 180, it is to be understood that the surface of cam 149 ~ c~50065 need not ~e planar, it may be concave or convex. lhe require-ment of the surfaces of the cams 180 and 149 is that they should be so formed that as the shaft 69 rotates, the value ~f "Y" should vary by a minimal amount while the claw 184 is disposed in a perforation, ~hat is~ during a pull-down stroke and that the claw should enter and leave a perforation in directions substantially perpendicular to the film plane.
Figure 6 shows plots of the path of Point P of the shuttle teeth 184 for 35mm, Super 8, and regular ~ filmr ~0 The degree values indicated in Figure 6 correspond to eccentric drive shaft 69 angle 9 as shown in Figure 5. For 35mm film, the eccentricity e ~f the eccentric drive shaft 69 is 94.2 mils. For Super 8 film, the eccentricity of eccentric drive shaft 69 is 84.0 mils. For regular 8mm film, the eccentricity Df eccentric drive shaft 69 is 75.6 mils. These values are slightly more than one half film pitch to allow for bearing clearance and to provide free entry of teeth 184.
In order ~o eliminate the necessity of temporarily ~plicing the end of a new film to the end of an expiring film, or provi~ing the end of a new web with one ~r more perforations to insure its being handled by the perforator, this perforator ~nc~rporates an automatic threading mechanism which will thread unperforated film to and through the punch mechanism and to the ~huttle mechanism. This automatic threading mechanism inter-mittently advances the film to the punch and shuttle mechanisms by intermittently frictionally engaging the film and ad-vancing it in increments substantially equal to the perforation ~ o~o~s pitch and the advancing stroke of the shuttle me~hanism.
In order to investigate this automatic threading mechanism in more detail, let us return our consideration to Figures 1, 3 and 7. Shaft 228 is rotatably journaled in bear-ings 230 (as shown in Figure 7) which are supported by base block 20. Arm 232 is rigidly at~ached to shaft 228 by bolt 234 (as shown in Figure 1). Arm 238 is attached to arm 232 by bearing stud 236 and a bearing assembly, which ~11 be de-scribed in more detail with reference to Figure 8. Engagement arm or shuttle arm 240 is attached to arm 238 by shaft 242 and a bearing assembly which will be discussed in more detail be-l~w. One end of engagement arm 240 rides on eccentric split ball bearing 119 (as shown ln Figure 2) in an engaged position.
One end of spring 246 is hooked onto spring anchor pin 244 which is attached to arm 232. The other end of spring 246 hooks around pin 248 which is ri~idly attached to front side plate 25. The purpose of spring 246 is to urge arm 232 and shaft 228 in a clockwise direction. One end of spring 252 hooks around pin 250 which is rigidly attached to arm 238. The other end of sprîng 252 is hooked around pin 254 which is rigid-ly attached to engagement shuttle arm 240. The ~?~lrpose of spring 252 is to urge the left end of engagement arm 240 in a counter-clockwise direction in relation ~o arm 238.
Stop 256 is attaehed to front side plate 25 by bolts 258 (~s shown in Figure 7). The purpose of stop 256 is to limit the counter-clockwise travel of the right-hand end Df engagement arm 240 when the thread-up shuttle is ~n the ~ 22 -l~S006S

disengagcd position as shown in Figure 1. Stop p~ns 262 and 266 are rigidly attached to base block 20 to limit the tra~el of arm 232. To the other end of shaft 228 is attached bracket 268 (as shown in Figure 33. Flat spring 270 (see Figure 3) is attached to bracket 268 by screw 272 (see Figure 3).
In order to see how the thread-up shuttle mechanism is placed in the operative position, let us turn our attention t~ Figures 1 and 3, in which the thread-up shuttle is presently sh~wn in the disengaged or inoperative position. In order to place it in the operative position, an electrically energized solenoid 302 (see Figure 12) is energized which urges the top of flat spring 270 (as shown in Figure 3) in the counter-c~ockwise direction. The purpose of flat spring 270 is to allow for over tra~el of solenoid 302. The counter-elockwise motion of flat spring 270 rotates bracket 268 in the counter-cl~c~wise direction. Since bracket 268 is ronnected to shaft 228 by screw 272, shaft 228 also rotates in the counter-clock-wise dlrection. Arm 232 will rotate in the counter~clockwise direction until set screw 264 is Limited in its travel by stop pin 266. Arm 240 wqll now be lowered away from stop 256 thus allowing spring 252 to urge the left end of engagement arm 240 into contact ~th ball bearing 119 (as shown in Figure 2). As the left end of engagement arm 240 rides on eccentric bearing 119 the right end of engagement arm 240 will move in a path such that it frictionally grips and advances the web to and past the punching position in increments substan-1~50065 tially equal to one perforation pitch. The frictional means by which the film is gripped by the right end of en~agement arm 24~ will be discussed in more detail below ~th reference t~ ~igure 9.
In order to disengage the thread-up shuttle assembly, the electrical solenoid 302 when de~energized will cease to press on flat spring 270. Spring 246 will then urge arm 232 in a clockwise direction causing shaft 242 ~o move in a direction such that the film is disengaged~ the arm 240 in so moving striking stop 256 causing the left end of engagement arm 240 to move outof engagement with eccentric ball bearing 119 (as shown in Figure 2).
As shown in Figure 8, the lower end of arm 238 is rotatably journaled to arm 232 by a bearing assembly com-prising bearing stud 236 suitably held by two ball bearings 275 and spacers 277. Shaft 242 is journaled to rotate in the upper end of arm 238 through a bearing assembly comprising two ball bearings 279 and spacer 281. Engagement arm 240 is ~ress itted onto shaft 24Z.
Figure 9 shows that stop arm 283 and one end of flat springs 285 are attached to engagement arm 240 ~y bolts 287.
S~uttle pad 289 and stop arm 291 are attached to the other end of springs 285 by bolts 293. The bottom surface of shuttle pad 289 is covered with a high friction material, such as polyurethane, to further enhance the film driving action.
Four ball bearings 295 and two spacers 297 are attached to shaft 299 which is rigidly attached to apron member 188. As . - 24 -l(~S0065 sho~ ~n Figure 9 flat springs 285 in connection with stop arms 283 and 291 comprises a resilient breakal~ay connection causing shuttle pad 289 to move with the shuttle at all times except after the shuttle pad 289 moves into engagement with the face of the film, at which time engagement arm 240 moves relative to shuttle pad 289 and stresses springs 285 which resil~ently urge shuttle pad 289 into engagemen~ ~ith the film.
As ~he left end of engagement arm 240 rides on eccentric bearing 119 (as shown in ~igure 2) the right end of engagement arm 240 causes shuttle pad 289 to move through the open top ~ the film guideway and into pressing engagement with the face of the film at the beginning of and during the film ad-vancing stroke ~ the shuttle to advance the film. At the end of the film advancing stroke the right end of engagement arm 240 moves so as to r~tract shuttle pad 289 from engage-ment with the film and hold it retracted during the return stroke.
In order to determine the correct relationship be-tween the locations of eccentric drive shaft 699 bearing stud 236, shaft 242, and ball bearings 295-let us look at a schematic of the geometry as shown in Figure 11. Figure 11 8hows schematical ly the side view ~f the zone of the film path to be occupied by the thread-up shuttle. The film path with free turning ball bearings 295 just below the film surface end the location of eccentric drive shaft 69 are known. We must establish the location of shaft 242 which swings about the bearing stud 236 and the eccentricity e at the driver required to obtain the desired film advance T, - 2~ -c`
l~DS006$
The right end of engagement arm 240, shown in Figure 11 by dotted line, is fitted ~ith the shu~tle pad 289 (see also Figure 9) which is spring loaded agains~ a stop and so adjusted that it pinches the film against ball bearings 295 during approximately one-half of the Pccentric rotation and l~fts away from the film for the remainder of the time when the thread-up shuttle mechanism is in its operative con-dition. It is also understood t~ t the left end of engagement ~nm 240 (as shown in F~gure 13 engages the split ball bearing 119 (as shown in Figure 2) during the time required for thread-up and then is disengaged and does not contact the eccentric bearing 119 or the film during the remainder of perforating the roll of film.
It is necessary that the motion of shut~le pad 289 be essentially perpendicular to the plane of the film at the instant of making contact and at the instant of leaving the film. This produces the most accurate control of the film mot~on as no longitudinal motion ta~es place during the short interval of time ~en pinching pressure is being established or released. We therefore loca~e shaft 242 in the plane of the film as extended beyond the location of ball bearings 295 (as shown in Figure 11). The length of the arm from point A on shuttle pad 289 to shaft 242 is of secondary importance but it has been found well to make the distance X from the cen~er of shaft 242 to point A a little shorter than the distance Y
between the center of eccentr;c drive shaft 69 and shaft 242.

. - 26 -~ ~5~D~6 5 This produc~s a motion at the right end ~ engagement arm 240 which is essentialLy elliptical in shape, the minor axis being perpendicular to the film.
Now draw the line from the center of rotation of bearings 295 which is perpendicular to the film and also draw the line from the center of rotation of eccentric shaft 69 which is perpendicular t~ the line drawn from the center of shaft 242 to the center of eccentric drive shaft 69. The intersection of these lines defines the point I. It can be seen that the two extreme positions of the travel of engage-ment arm 240 can be analyzed as if it had physically been con-~trained to rotate about point I as an axis. The center of the eccentric bearing 119 (as shown in Figure 3~ on the eccen-tric shaft 69, the cent~r of shaft 242, and the point A at their extreme positions all move a distance corresponding to the angle~ measured about axis I. It follows directly that the eccentric travel 2e must be equal to the desired film travel T multiplied by the ratio of the lengths of the li~e from the center of eccentric shaft 69 to point I divided by the distance from point A to point I. It also follows that the advance angle is 180~+ a . The phase relation between eccentric position and film travel is also readily understood from this construction.
The moving pivot, shaft 2425 can be constrained by ~n arm pivoted at I, however it is usually not practical to ~perate at this great a distance. The action is entirely :~0S~i5 satisfactory if another pivot point such as pvint 236 is chosen s~ long as the p~int 236 falls on the line between the center of shaft 242 at its mid stroke and point I.
Strictly speaking the center of shaft 242 d~es not remain in the plane of the film ~ ~ause the line between the center of shaft 242 and the center of bearing stud 236 ~s not perpendicular to the film plane at ball bearings 295.
However the plane of the shuttl e pad 289 slightly modifies the film path and does the cla~.ping or lifting off strictly in a direction perpendicular to itself.
The automatic threading mechanism described above is c~mbined with the perf~rator so that it can be selectively en-gaged and will automatical~y disengage when the end of a new film reaches a point in the film path following the shuttle mechanism and, ater the shuttle teeth 184 have contr~l of the film. To understand this operation better, attention is called t~ Figure 12, which shows the thread-up shuttle electrical con-trol diagram. There is no film in the perforator when it is desired to begin the thread-up sequence. Thread-up button 300 is pressed and then released. Time delay relay TDR is energized, which closes its normally open switch TDR-l. Solenoid 302 is energized and pushes against spring 270 to rotate shaft 228 counter-clockwise thus causing engagement arm 240 to come into engagement with ball bearing 119 and be driven by eccentric drive shaft 69, hence putting the thread-up mechanism in the en-gaged or operative condition as described in detail above. Re-~ 0.50065 lay Rl simultaneously is energized which clQses its normally ~pen switch Rl-l. As normally opened switch Rl-l is closed, motor ~ driving eccentric shaft 69 begins running at 1800 rpm.
The end of a roll of unperforated film is then inserted intu the channel between the supply sid~ film apron 188 (as ~hown in Figure 3) and supply side film apron cover 190 (as sho~
~n Figure,3). The thread-up shuttle mechanism then advances the fiLm in the manner described in detail above until normally closed switch 307 in the film path defined by the take-up side film apro~ 192 and take-up film apron cover 194 (as shown in Figure 3) is reached by the film. When the film reaches normal-ly closed switch 307 it opens it. This causes solen~id 302 tu become de-energized thus allowing engagement arm 240 (as shown in Figure 2) to move out of contact with ball bearing 119 (as shown in Figure 2) hence putting the thread-up shuttle mechanism in the inoperative cvndition as described in detail above. Time delay relay TDR then starts a time delay of approx-imately 10 seconds. After the 10 seconds has elapsed, time delay relay TDR is de-energized which in t~rn opens its switch TDR-l which de-energizes rel~y Rl causing its switch to revert to the position shown, causing m~tor M to stop. The thread-up Dpera~
tion is now complete.
After the threading operation is complete and the high-speed shuttle mechanism is capable ~ c~ntrolling the film, the m~chine is put in high speed operation in ~he following manner.
Again referring to Figure 12, high speed start button 310 is 29 ~

~ Q5l)~S
pressed and released. Relay R2 is energized which makes its nor~ally open switch R2-1, The closing of switch R2-1 turns on 400 Hz supply 313 which powers motor 306 at 12,000 rpm through normally closed switch Rl-l. The fllm is then perforated in the manner described ln detail above. LDcated in the film path adjacent t~ switch 307 ~here is a second switch 3149 normally open, which is closed when film is in this p~si tion ~f the film path but which normally opens when there is nD ilm in this portion ~f the film path. Since film has 10 alrèady been threaded through the perforator past this switch 314 it is closed which allows the m~t~r M to ~perate at high speed. W~en the trailing end of the film passes switch 314 it returns to its normally open state to de-energîze relay R2 and this in turn allows its switch R2-1 to return to the normal ly open condition shown and cut off the 400 Hz supply 313 where-upon the mot~r stops. The perforation is then complete.
In order to see how the film is guided to and through the perforating station, let us look at Figure 10. As shown in detail in Figure 10, edge guide buttons 325 are attached to flat spring 327 which is attached at its center in spaced relation ~o the front side plate 25 by means of a clamp screw 339 and by spacer 343. Set screws 32g which are ~hreaded into front side plate 25 press agains~ spring 327 thus controlling its position. Edge guide buttons 331 are attached to spring 333 which is attached at its center in spaced relation to the back side plate 27 by means of the clamp screw 341 and spacer 345. Spring 333 is maintained in position by compression 1~50065 springs 335 which are pressed against by set screws 337 threaded into back side plate 27. The purpose of edge guide buttons 325 and 331 and the spring arrangement is to control the lateral position of the film as it goes through the per-forating sequence. Another advantage of the gate configura-ti~n as shown in Figure lO is that front die holder 196 and rear die holder 198 are cur~Ted such tha~ they define a curved path for the film approaching and leaving the perforating position so as to maintain the film in a bowed condition for overcoming any transverse curl the film might possess at the time it is per~orated.
Also, as shown in Figure 10, die 349 and pilot die 347 are pressed into die holders 196 and 198. When the machine is perforating~ punches 130 fit with very small clearance intv dies 349 and pilot pins 134 fit loosely into pilot dies 347.
While an embDdiment of the perforator has been described in w~ich the elongated web to be perforated is a photographic motion picture film, it will be understood that other w~b materials, e.g., paper, may be perforated by apparatus in accord-ance with the present invention and such perforated webs of paper ~r other material may be advanced by a claw device in accordance with the present invention. Also, w~ile the con-~ex cam has been described as being associated with the shuttle arm 102 and the flat cam as being mounted by the spring members 140, 156, it is to be understood that the convex cam could be m~unted Dn the s~ring members and the flat cam could be associa-ted with the shuttle arm.

~oso~s Reference is now made to Figure 13 which illustrates a simplified embodiment of my novel shuttle means which is particularly adapted for use in mDtion pi~ture cameras ~here the intermittent pull-down speeds required are relatively sl~w. Since motion picture cameras, particularly those ~ntended for ama~eur use, do not require such long ~esign life, probably less than 100 hours as compared to 16,000 hours for the perforator, it is not necessary to eliminate slip between the rocker and flat cams 180 and 149 respectively. In fact, the flat cam need not be mounted in a moveable carriage or driven by an eccentric through the U-shaped coupling spring 170, but may be stationary with attendent simplicity and cos~ reduc-tion. Also simple bearings will suffice in place of the ball bearings. Referring to Figure 13, we see that drive shaft 355 is suitably journaled in bearings (not shown) which are mounted in frame me~.bers (not shown3. Drive shaft 355 receives its power input from a motor (not shown) in the direction shown. Pin 357 is rigidly attached t~ drive shaft 355. ~d-~ance arm 359 is suitably journaled to pin 357 by a beàring assembly (not shown). Advance arm 359 contains an arcuate cam surface 180 which rides against stationary flat ca~ 149 , which is rigidly attached to frame member 364 by suitable means (not shown). The resulting path of point P on the shuttle t~oth portion 184 of advance arm 359 is shown by the dashed line in Figure 13. The shuttle tcoth portion of advànce arm 35g suitably engages the perforations in the film so as to ad-vance it the desired amount. It can be appreciated that the ~ 0~ 6 5 csms and eccentric drive can be placed to one side of the film with only shuttle to~th 184 being off-set to align ~ith one of the rows of perforations in the film. In such a case the flat cam surface could be in the same plane as that of the film.
The stationary flat cam scheme sho~ in Figure 13 is satisfactory for camera use since advance will take place durlng approximately 1/2 of one rotation of drive shaft 355.
For a projector it is necessary to interrupt the light beam three or more times for each frame advance to avoid flicker prcblems. As a result the shuttle when ~esigned for use in a motion picture projector must advance the ilm in about 1/6 or less of the time allocated for one frame at the - usual projection frame rates (16-24 per second). The shuttle mechanism described for the perforator and the stationary flat cam version shown in Figure 13 for motion picture cameras require nearly one-half of the frame period. A
~uitable embodiment adapted for use in motion picture pro-~ectors can easily be prDvided by using the "skip-frame"
principle.
Figure 14 shows a modification of the perforator high speed shuttle de~ice as it might be applied to an am2teur motion picture projector. Drive sha~t 355 is suita-bly journaled in bearings (not shown) which are moun~ed in frame members (not shown). Drive shaft 355 receives its power input from a motor (not shown)5 and is rotated in the direction show~. Pin 357 is rigidly attached to shaft ~ s~
355 . Advance arm 359 is a~ached to pin 357 through a ~uitable bearing assembly (n~t shol~). Gear 387 is m~unted on shaft 355 by pins (n~ sho~). Gear 389 is mounted on shaft 388 which is suitably journaled to rotate through bearings (not sho ~ which are mounted in the supporting frame members (not sho~n). Gear 389 meshes with gear 387 and provides the necessary speed reduction needed to obtain the proper skip frame rate. Peripheral 391 is rigidly mounted to gear 389 by pins (not shol~n). Flat cam 149 is ~ttached to mounting bracket 383 through pin 381 ~nd a suitable bear-ing assembly (not shown). Mounting bracket 383 is attached to frame member 385 by suitable means (not shown). One end of spring 393 is hooked around pin 395, which is rigidly ~ttached to flat cam 149 to the left of pin 381. The ~ther end of spring 393 is hooked around bracket 399 which is attached to support member 401 by suitable means (no~
~hown). The purpose of spring 393 is to hold the left end of flat cam 149 in contact with cam 391. Advance arm 359 has a peripheral cam surface 180 which rides in contact with the portion of flat cam 149 that is to the right of pivot pin 381. One end of spring 361 hooks around pin 362 which is rigidly sttached to advance arm 359 r The other end of spring 361 hooks around bracket 365 which is rigidly attached to support member 401 by suitable means ~ot shown). The purpose of spring 361 is to hold the cam 180 of advance arm 359 in contact with flat cam 149 . The ~ - 34 -arcuate cam surface 180 on advance arm 359 is of such a shape so as to cause point P on the shuttle tooth portion 184 of advance arm 359 to engage a perforation in the film and to cause point P to follow a path approximated by the dashed line in Figure 14. Cam 391 has an arcuate sur-face such that point P engages the perforation and then pro-perly disengages the perfora~ion during one rotation of drive shaft 355 . The shape of cam 391 alss is such that it urges the left end of flat cam 149 in such a way that point P will not engage the perforation of the film during the subsequent two rotations of drive shaft 355 . Depend-ing upon the gear ratio, any number of skipped strokes can be provided. It should be noted that flat cam 149 and 1~ r the arcuate cam portion 180 of advance arm 359 can be placed to one side of the film with only the shuttle tooth 184 being off-set to align with the row of perforations in the film strip. In such a case the flat cam surface could be in the same plane as that of the film.
The film intermittent drive on the perforator used during thread-up is a shuttling device which is designed : to drive a film which has no perforations. Figure 15 shows B modification of the thread-up shuttle design that may be used in a motion picture camera that can accommodate per-forated or unperforated film.

~ 34a 1~500~5 Referring in detail to Figure 15, we see that drive shaft 415 is suitably journaled to rotate in bearings (not shown) which are mounted to fixed frame members (not shown). Drive shaft 415 receives its power input from a motor ~not shown) in the direction shown. Pin 417 is rigid~y ~ttached to eccen~ric drive shaft 415. S~uttle ar~ 240 is rotatably attached to pin 417 through a suitable bearing assembly (not shown). One end of arm 238 is attached to shuttle arm 240 by pin 242 and a suitable bearing assembly (not shown). The other end of arm 238 is rotatably attached to bracket 427 by pin 236 and a suitable bearing assembly (not shown). Bracket 427 is attached to frame member 429 by suitable means (not shown). Arm 431 is attached to arm 238 by link connection 433 having either end pivots or end connections. The bottom end of arm 431 is attached to bracket 437 through pin 435 and a suitable bearing assembly (not shown). Bracket 437 is attached to frame member 429 ~y suitable means (not shown). The top end of arm 431 ~nd pad surface A may be covered by a high-friction material~
such as polyurethane, to improve the film driving force with less spring pressure. The upper surface of arm 431 i~ trimmed accurately to provide optimum driving geometry and ~s mounted just a few thousandths of an inch below the ~ilm sur~ce. Link connection 433 is so located in relation to ~ 34b ~

pins 236' and 435 as to produce the desired film advance travel of the upper surface of arm 431, The advanta~es of the embodi-ment shown in Figure 13 is the added positive dr~ving force impar~ed to the film. Thi~ leads to hlgh E?recision as w~s the case in one experimental perfor~tor in whir.h this was the sole mesns of advance and pitch determlnation of the resul ting film. Operation with lower clamp forces or high speed or both ~re improved by this arrangement ~ The locat~ ons of the center of eccentric drive shaft 415, pin 242', pin 236 ? and pin 435 10 are obtained by the sa~e considerations as described sbove in arriving at the corresponding poin~ ~ F~gure 11, As eccentric drive shaft 415 ro~tes in the direction shown ~n Figure 15 the film is advanced in the direction shown by the arrow in Figure 15. Intermitt~nt advanee of film F w~ll take place during approximately 1/2 o~ the rotation of drive shaft 415. The dr~ving control pad A is suitably attached to arm 240' by means of resilient con~ections and a stop as described in relation to Figure 9.
Figure 16 shows a schema~ic of a further modifi-cation of the perforator thread-up shuttle mechanism that might be used in an amateur motion picture ~rojector application. Drive shaft. 415~ i~ suitably journa~ed to rotate in bearings (not shown~ which are mounted on fixed frame members (not show~n) . Drive shaft 415 ' receives its power input from a mo~or (not shown) in the direction shownO
Pin 417 ' is rigidly attached eccentric~lly to drive sh~ft 415'. Shuttle arm 240" is rotatably journaled to pirl '~17 ' ~ .0~l)06S
throu~h a suitable bearlng assembly (not shown~, Genr 451 is mounted on shaft 415' w~ich is suitably ~ourn~led to ro~ate in the frame members (not shown3, Cam 457 is rigidly attached to gear 453 by pins (not shown). Arm 238', is rotatably journaled ~o shuttle arm 240" by pin 242" which in turn is rigidly attached to shuttle arm 240" by ~ sui~cable bear~ng assembly (not shown), The other end of arm 238" is pivotally attached to cam follower arm 465 by pin 463 and a 8uitable bearing assembly (not sh~wn), The righ~ hand end of ~0 cam follower arm 465 is pivotal ly attached to bracket 467 through pin 466 and a suitable bearing assembly (not shown3.
Br~cket 467 is attached to support member 429' by any suitable means (not shown). The purpose of spring 471 is to hold the left end of cam follower arm 465 in con~act with the peripheral ~urface of cam 457. Arm 431' is attached to arm 238" by link connection 433' which can have either end pivo~s or flexible end connections. The bottom end of arm 431' is attached to bracket 437 ' through pin 435 ' and a suitable bearing assembly (not shown~. Bracket 437' is rigidly attached to support member 429' by any suitable means (not shown). As drive shaft 415 i~ driven in the direction shown in Figure 16 film F is advanced intermittently in the direction shown by the arrow in Figure 16. The purpose of cam 457 is to urge the left end of cam follower arm 465 in such a manner so ~hat the relative location of pin~ 463, 242" and 435' is altered ~o that the film is intermittently advanced ~ dist~nce equal - 3~ -~ 0sa065 to one frame pitch during one rotation of drive shaft 415 8nd not advanced during the subsequent two rotatlons of drive shaft 415'. Depending upon the gear rativ any number of skipped strokes oan be provided, The relati~e locations of drive shaft 415', pin 242", pin 463 ~nd pin 435' are determined in the same manner as above described for the embodiment shown in Figure 11. The location of link connection 433' in relation to pin 463 on cam ollower arm 465 and pin 435' is chosen such that the desired film travel is obtained at the film advancing statlon, The driving contact pad A is sui~ably attached to arm 240" by means of resilient connections and a stop as described in ~el~tion to Figure 9.
Figure 17 shows a further modification of the thread-up shuttle used in the perforating device as it might apply to an amateur motion picture camera that can accommodate either perforated or unperforated film. Dri~e ~haft 490 is suitably journaled to rotate through bearings ~not shown) which are mounted in a frame support (not shown~.
Eccentric pin 492 is rigidly attached to drive shaft 490.
Shuttle arm 494 is attached to drive shaft 490 through pin 492 and a suitable bearing assembly (not shown). The other end of shuttle arm 494 is pivotally attached to ~rm 498 at point 496 and terminates in a gripper finger - 497 which is adapted to pinch the film between itself ~nd top edge of arm 498 d~ring the ~ilm advance stroke. Finger o 37 _ 06s 497 wlth its contact p~d A is resiliently connected to arm 494 with a stop arranged to lift A from the film for the return stroke as discussed in connection with Figure 9, The bottom of arm 498 is attached to bracket 502 through pin 500 in a suitablè bearing assembly (not shown). Bracket 502 is rigidly attached ~o support me~ber 504 by any suitable manner (not shown), Preferably the angle between the lines formed between pin 500 and the center of drive shaft 490 and . ~ line drawn between the center of drive shaft 490 and pin 496 should be approximately 90 for optimum operation. In like , manner the line drawn between pin 500 and point A where the film is gripped by the gripper 497 and to top of arm 4~8 should be at approximately 90 to ~he tangent to the film path ~s drawn a~ point A, The pivot center 496 should preferably be on the same tangent to the film path. The embodiment shown in Figure 17 may be preferable to that shown in Figure 15 where ~pace requirements might be restrict~ng for some applications.
As drive shaft 4gO rotates in the direction shown in Figure 17, the film is advanced intermittently in the direction shown by the arrow in Figure 17. Note that this intermittent film travel is opposite in direction to the application shown in ~igure 15. The geometry can be arranged with equal ease and 8implicity such that pi~ot 496 ~alls to the left of point A
in which case the film is advanced to the left for the direction of rotation shown on Figure 17, In the modification shown in - F~gure 17, arm 498 t~kes the place o arms 238 and 431 and link connection 433 in the configuration as shown in Figure 15.

;

~ S0~65 In the camera or perforator application, as shown in Figure 17, it is understood that the gripper 497 on the right end of ~huttle arm 494 pinches the film against the top of arm 498 during approximately one-half of the eccentric rotation and l~fts sway from the film for the remainder of the time.
Figure 18 shows a further embodiment of the thre~d-up ~huttle of the perforator as it might be modified to operate as an inter~ittent feed applicable to an amateur motion picture projector. Eccentric pin 492' is rigidly attached to drive fihaft 490' which is suitably journaled to rotate in bearings (n~t shown) which are mounted in a support member (not shown).
`:
The left end of shuttle arm 494' is a~tached to drive sh~ft 490~ by pin 492' and a suitable bearing assembly (not shown~.
Gear 516 is fixedly mounted on drive shaft 490' and gear 518 is rigidly moun.ed on sha~t 520 which is suitably journ~led to rotate in bearings (not shown) which are suitably mounted in the support frame (not shown), Gear 518 meshes with gear 516 to give the desired 3 :1 or other ratio of speed reduction necessary for skip frame operation as required in a motion picture projector. Cam 522 is mounted rigidly on gear 518 by pins (not ~hown). The right end of shuttle arm 494' is pivotally attached to arm 498' by pin 496' and terminates in a gripper ~inger 437' which is adapted to pinch the film between itself and ~he top edge of arm 498' during ~he film advance stroke . Finger 497' with its contact pad A' i5 resillen~ly connected to arm 494' with a stop arranged to lift A' from tlle film for the return stroke as discussed in connection with Figure 9.

1050~S
The bottom end of arm 498' is attached to bracket 502' through pin 500' in a sultab~e bearlng assemblyO
Bracket 502'is rigidly attached to suppor~ member 504~ by any ~u~table means (not sho~m)O The right end of cam follower arm 530 is pivotally at~ached to bracket 534 by pin 532 and bracket 534 is rigidly m~unted to support member 504~ by any suita~le means (not shown)O One end of spring 538 is hooked around pin 540 att~ched to c~m follower arm 530 and the other end of spring 538 is h~oked onto bra~ket 542 which is rigidly mounted to sltpport member 504' by any suitable means (not shown)O The bottom end of arm 544 is pivotally attached to cam follower arm 530 through pin 546 and a su~table bearing assembly (not ~hown)O Pin 548 is rigidly attached to arm 4989and fit~ through a slot in arm 544 so that arm3 544 and 4981 m~y have relati~e motion in the direction of the slot only, The purpose of spring 538 i8 to ~Fge ca~ follower arm 530 into continuous con~act . . .
with th~ peripheral surfac~ of cam 5220 The surface of cam 522 is of such a shape tha~ during the first rotaticn of shaft 490' the film is gripped a~ point A' be~ween the gripper portion 497' of shuttle arm 494' ~nd the top of ~rm 4g8' during one-half of the shaft rotation and lifts away frcm the film f~r the remainder of the timeO During the subsequent two rotations of shaft ~90', the sursce vf cam 522 is such that it urges cam follower arm 530 upwards which in turn czuses pin 546 and arm 544 to move upwards~
Arm 54~ then contact~- arm 497' and raises it sufficiently - 40 ~

~ S~ ~6S
to prevent the film from being advanced during the su~sequent revolutions of drive shaft 490l. Depending upon the gear ratio, any number of skipped strokes can be provided. Wlth the direction of rotation shown in Figure 18 for drive shaft 490', the film is advanced intermit-tently to the right as sho~m by the arrow. The pivot point 496' can alternatively be located ~o the left of point A' reversing the film tr~vel direction as explained for Figure - . 17. The top surface of arm 498 ' in the vicinity of point ~ engaged by pad surface A' may be covered with a high friction material, such as polyurethane, to further enhance the film advancing action. The region ~f arm 498' around point A' is carefully trimmed and mounted a few thousandths of an inch below the film surface.
It may ~e desirable to locate pin 546 substantially in line with pin 500' in order to prevent unwanted relative motion between anm 544 and arm 598'. The arrangement shown in Figure 18 is pr~sented for the sake of clarity.
The in~ention has been described in detail with particular reference to preferred embodiment thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention.

Claims (3)

1. A film advancing assembly for intermittently feeding an unperforated web strip through a given path comprising the combination of:
1) a web guideway defining a portion of said path and including:
a) support means for supporting one face of the web, said support means including a roller to facilitate movement of said web, b) edge guides for guiding the edges of said web, and c) means for providing access to the other face of said web;
2) a shuttle reciprocatable through a path including a web advancing stroke and a return stroke;
3) a friction pad attached to said shuttle to reciprocate therewith;
4) means for reciprocating said shuttle and causing said friction pad to move, via said access means, into pressing engagement with the other face of said web at the beginning of and during the web advancing stroke of said shuttle to advance said web,said pad retracting from engagement with said web during said return stroke.

2, A film advancing assembly as defined in Claim 1, wherein said shuttle comprises an elongated arm pivoted intermediate its ends on a movable pivot, said friction pad attached to one end of said arm and the other end of said arm connected with an eccentric.

3. A film advancing assembly as defined in Claim 2, wherein the attachment of the friction pad to said shuttle comprises a resilient break-away connection causing the pad to move with the shuttle at all times except after the pad moves into engagement with the other face of the web, at which time the shuttle moves relative to the pad and stresses a spring which resiliently urges the pad into engagement with the web.